The present invention is directed to coatings for ammonium nitrate prills that comprises blends of petroleum products combining the blends with the surface of and penetrating the open pores of the prill to increase tackification of the prill.
A problem in the ammonium nitrate prill art is coating porous and dense prills so that the prills become tackified and remain free flowing. Past coatings have been engineered to make prills free flowing. As a consequence of the free flowing nature of these prills, ammonium nitrate dust is created causing environmental, health, and operational problems. In addition these past coatings do not prolong the shelf life of the ammonium nitrate prill. The blends act as a fuel to the explosion and as a stabilizing medium to the emulsion.
Examples of other attempts to prolong the life of prills are found in U.S. Pat. No. 4,555,278 disclosing the use of an anionic emulsifying agent combined with a fatty acid used to stabilize the prill in a water-in-oil emulsion. U.S. Pat. No. 4,615,751 discloses an explosive which contains a water-resistant agent for inhibiting deterioration of the ammonium nitrate prill.
The present invention uses blends of petroleum products to coat ammonium nitrate prills, both porous and dense. These coated prills are found useful since they improve tackification, reduce dust, and prolong shelf life. As those skilled in this art will recognize this invention is found particularly useful for up-hole loading and is strongly indicated as useful for down-hole loading, in particular, through wet holes.